I have an issue with the Power Button. But another thing I forgot to mention is when the phone is turn off, I never know if the phone is at rest or died. I just realized this morning after I power off the phone it went dead from there or during incoming call/emails or text messages. I found out the phone is dead when I check messages on my laptop computer. Have no issue when the phone is connected to a charger.
It happened before when there is incoming messages or call and the phone won't power on. Is this phone built not to last.

I never drop the phone ever or have and damage on it since the first day I owned it.

Thank you.